This invention pertains to a novel dosage form useful for delayed-drug delivery. More specifically, the invention relates to a dosage form that after administration of the dosage form is followed by a drug-free period, which dosage form at this later time delivers a dose of drug for delayed therapy. The drug is delivered during the drug-delivery period at a controlled rate over time. The invention pertains also to an initial pulse of drug followed by a drug-free interval, which latter interval is followed by a drug delivery period over time. The invention concerns also a method of delayed-drug therapy by administering a dosage form that delays the onset of drug delivery, and after the drug-free interval delivers a drug for its therapeutic effect.
A critical need exists for a dosage form that makes available at a later time a drug to satisfy a therapeutic demand. The demand can arise during a circadian or chronological cycle, or the demand can arise for producing a therapeutic effect a later time, such as during the morning hours. For examples, many patients with myocardial infarction exhibit a clinical incidence of this syndrome that shows a circadian distribution with high frequency in the morning hours between 4:00 a.m. and 9:00 a.m., as reported in The American Journal of Cardiology, Vol. 62, pages 635 to 637, 1988; Circulation, Vol. 82, pages 897 to 902, 1990; and Heart Disease, Vol. 2, pages 1234 to 1235, 1988. Yet, the medical art, previously lacked a dosage form for administering a drug that provides therapy for this application during these critical hours.
There are dosage forms known to the prior art for delivering a drug continuously over time, such as disclosed in U.S. Pat. No. 4,327,725 issued to Cortese and Theeuwes, and in U.S. Pat. Nos. 4,612,00; 4,765,989; and 4,783,337 issued to Wong, Barclay, Deters and Theeuwes. The dosage forms disclosed in these patents comprise a semipermeable wall that surrounds a compartment. The compartment comprises a drug formulation, and in contact with the drug formulation, a displacement member that pushes the drug formulation from the dosage form. These dosage forms operate by imbibing fluid through the semipermeable wall into the compartment, wherein the fluid contacts and motivates the displacement member to consume space and thereby pushes the drug formulation from the dosage form. These dosage forms operate successfully for their intended use, and they can deliver many different to deliver drugs for their intended purpose. One limitation, however, associated with these dosage forms, consists in the dosage form immediate delivery of drug of a drug recipient. That is, the dosage forms do not provide for the delayed delivery of a drug to satisfy a future therapeutic need.
It is immediately apparent in the light of the above presentation that a pressing need exists for a dosage form that can delay the delivery of a drug to provide a drug-free interval and then deliver a dose of drug. It will be appreciated by those versed in the dispensing art, that if a novel and unique dosage form is made available for executing a therapeutic program comprising a drug-free interval followed by a drug-delivery interval, or a pulsed dose followed by drug-free time, followed by drug delivery time, such a delayed drug-delivery dosage form would have a practical application, and it would also represent a valuable contribution to the medical arts.
Accordingly, in view of the above presentation, it is an immediate object of this invention to provide a novel and useful dosage form that represents an unexpected improvement in the dispensing art and substantially overcomes the disadvantages known to the prior art.
Another object of the present invention is to provide a dosage form that can delay the delivery of a beneficial drug.
Another object of the present invention is to provide a dosage form that can delay the delivery of the drug from the dosage form, and then deliver a dose of the drug.
Another object of the present invention is to provide a novel dosage form comprising means for delaying the delivery of drug, followed by means for delivering at a later time a dose of drug.
Another object of the present invention is to provide a dosage form that delivery a pulsed dose of drug, followed by a drug-free interval, followed by a drug delivery interval to provide unexpected beneficial therapy.
Another object of the present invention is to provide a novel dosage form comprising means for delaying the delivery of drug for 30 minutes up to 7.0 hours from a dosage form, usually 30 minutes to 4.5 hours.
Another object of the present invention is to provide a novel dosage form that overcomes the limited functionality of conventional dosage tablets, and which novel dosage form can perform a drug program comprising a drug-free period for a duration as needed, and then to provide a drug-delivery period as needed for a time to achieve a desired therapeutic program.
Another object of the invention is to provide a dosage form comprising in a single dosage form a dosage of drug that is released by the dosage form at least two hours after the dosage form is administered to a drug recipient, and then delivers a drug for a later therapeutic effect.
Another object of the present invention is to provide a novel dosage form manufactured in the form of a drug delivery device comprising means for providing a drug-free interval, and means for then providing a future dose of drug.
Another object of the present invention is to provide a novel dosage form that makes available at a later time a drug for satisfying a need that can arise during a circadian or chronological cycle, or for providing a drug during the morning hours.
Another object of the invention is to provide a dosage form comprising a water-soluble, non-ionic polymer useful for providing delayed therapy.
Another object of the invention is to provide a therapeutic program comprising an instant dose of drug, followed by a drug-free interval and then a drug-delivery interval.
Another object of the invention is to provide morning therapy, also identified as AM-therapy, for providing therapy on a patient awakening and rising in the morning for good health.
Other objects, features and advantages of the invention will be more apparent to those versed in the dispensing art from the following specification, taken in conjunction with the drawing figures and the accompanying claims.